JP6686394B2 - Method for manufacturing semiconductor chip package - Google Patents

Description

  The present invention relates to a method of manufacturing a semiconductor chip package. Furthermore, the present invention relates to a resin composition, a sheet-shaped laminated material, a circuit board, and a semiconductor chip package.

  As the electronic industry has advanced in recent years and electronic devices have become more sophisticated, in semiconductor chip packages, it is possible to cope with an increase in the number of terminal electrodes of semiconductor chips and to realize a lighter, thinner, shorter and smaller package as a whole. Is required.

  In order to meet such demand, a flip-chip mounting technique has been proposed in which terminal electrodes of a semiconductor chip are pressure-bonded and connected onto a circuit board (see, for example, Patent Document 1).

JP, 2014-63881, A

  In order to further reduce the size, weight, and size of the semiconductor chip package, the pitch of the terminal electrodes of the semiconductor chip tends to be narrowed, and the pitch of the circuit wiring of the circuit board on which the semiconductor chip is mounted is also narrowed.

  In the flip-chip mounting technology, it is required to realize a method in which an insulating adhesive called NCP / NCF (Non-Conductive Paste / Film) is provided in advance on a circuit board, and a semiconductor chip is pressure-bonded to the insulating adhesive. There is. At that time, when mounting at a narrow pitch (for example, a pitch of 40 μm or less), it is necessary to use an insulating adhesive containing a flux agent in order to remove the oxide film formed on the surface of the fine circuit wiring of the circuit board. Although required, the present inventors have found that the use of an insulating adhesive containing a flux agent may significantly reduce the insulation reliability of the insulating layer of the circuit board.

  An object of the present invention is to provide a technique for manufacturing a semiconductor chip package having excellent insulation reliability of an insulating layer even when semiconductor chips are mounted on a circuit board at a narrow pitch.

  As a result of intensive studies on the above problems, the present inventors have found that the above problems can be solved by forming an insulating layer of a circuit board using a resin composition containing an inorganic ion scavenger, and the present invention It came to completion.

That is, the present invention includes the following contents.
[1] (I) A step of providing an insulating adhesive containing a flux agent on a circuit board including an insulating layer made of a cured product of the resin composition, and (II) a step of bonding a semiconductor chip to the circuit board. ,
The method for producing a semiconductor chip package, wherein the insulating layer containing the flux agent and in contact with the insulating adhesive containing a flux agent is made of a cured product of a resin composition containing an inorganic ion scavenger.
[2] A resin composition containing an inorganic ion scavenger contains (A) epoxy resin, (B) curing agent, (C) inorganic filler, and (D) inorganic ion scavenger,
The average particle diameter of the component (C) is 3 μm or less,
The average particle size of the component (D) is 1 μm or less,
The method according to [1], wherein the 40 μm thick, 4 cm square cured product obtained by thermosetting the resin composition at 190 ° C. for 90 minutes has a boiling water absorption of 0.6% by mass or less per hour.
[3] The method according to [2], wherein the component (B) contains at least one selected from an active ester curing agent and a cyanate ester curing agent.
[4] The method according to [2] or [3], wherein the component (C) contains silica.
[5] The component (D) contains one or more oxide hydrates or hydroxides selected from the group consisting of antimony, bismuth, zirconium, titanium, tin, magnesium and aluminum, [2]- The method according to any one of [4].
[6] The component (D) according to any one of [2] to [5], which contains two or more kinds of oxide hydrates or hydroxides selected from the group consisting of bismuth, zirconium, magnesium and aluminum. Method.
[7] The method according to any one of [1] to [6], wherein the circuit board has a circuit wiring having a minimum pitch of 40 μm or less.
[8] The method according to any one of [1] to [7], wherein the circuit board has embedded wiring.
[9] Before the step (I),
(I) a step of laminating a dry film on a support substrate and forming a pattern on the dry film (ii) a step of forming a conductor layer and peeling the dry film (iii) a support substrate on which the conductor layer is formed A step of providing a resin composition containing an inorganic ion scavenger and thermosetting the resin composition to form an insulating layer (iv) a step of peeling a supporting substrate to produce a circuit board, [1] to The method according to any of [8].
[10] A resin composition containing (A) an epoxy resin, (B) a curing agent, (C) an inorganic filler, and (D) an inorganic ion scavenger,
The average particle diameter of the component (C) is 3 μm or less,
The average particle size of the component (D) is 1 μm or less,
A resin composition having a boiling water absorption rate of 0.6% by mass or less per hour for a 40 μm thick, 4 cm square cured product obtained by thermosetting the resin composition at 190 ° C. for 90 minutes.
[11] The resin composition according to [10], wherein the component (B) contains at least one selected from an active ester curing agent and a cyanate ester curing agent.
[12] The resin composition according to [10] or [11], in which the component (C) contains silica.
[13] The component (D) contains one or more oxide hydrates or hydroxides selected from the group consisting of antimony, bismuth, zirconium, titanium, tin, magnesium and aluminum, [10]- The resin composition according to any one of [12].
[14] The component (D) according to any one of [10] to [13], which contains two or more kinds of oxide hydrates or hydroxides selected from the group consisting of bismuth, zirconium, magnesium and aluminum. Resin composition.
[15] The resin composition according to any one of [10] to [14], which is for an insulating layer of a circuit board.
[16] (I) Providing an insulating adhesive containing a flux agent on the circuit board, and (II) Bonding a semiconductor chip to the circuit board.
The resin composition according to any one of [10] to [15], which is used in a method for manufacturing a semiconductor chip package, including:
[17] The resin composition according to [15] or [16], wherein the circuit board is an interposer.
[18] A sheet-like laminated material including a layer of the resin composition according to any one of [10] to [17].
[19] A circuit board in which a surface on which a semiconductor chip is mounted is formed of an insulating layer made of a cured product of the resin composition according to any of [10] to [17].
[20] The circuit board according to [19], wherein the circuit board is a coreless board.
[21] The circuit board according to [19] or [20], which has a single insulating layer made of a cured product of a resin composition.
[22] The circuit board according to any one of [19] to [21], wherein the minimum pitch of circuit wiring is 40 μm or less.
[23] A semiconductor chip package in which a semiconductor chip is mounted on the circuit board according to any one of [19] to [22] via an insulating adhesive containing a flux agent.

  According to the present invention, it is possible to provide a technique for manufacturing a semiconductor chip package having excellent insulation reliability of an insulating layer even when semiconductor chips are mounted on a circuit board at a narrow pitch.

FIG. 1 is a schematic cross-sectional view for explaining a manufacturing process of a semiconductor chip package. FIG. 2 is a schematic cross-sectional view for explaining the manufacturing process of the semiconductor chip package. FIG. 3 is a schematic cross-sectional view for explaining the manufacturing process of the semiconductor chip package. FIG. 4 is a schematic cross-sectional view for explaining the manufacturing process of the semiconductor chip package. FIG. 5 is a schematic cross-sectional view for explaining the manufacturing process of the semiconductor chip package.

  Before describing the method for manufacturing a semiconductor chip package of the present invention in detail, the resin composition and sheet-like laminated material used in the method will be described.

[Resin composition]
In the method for manufacturing a semiconductor chip package of the present invention, the resin composition used for forming the insulating layer of the circuit board that is in contact with the insulating adhesive containing the flux agent contains an inorganic ion scavenger. And

  As described above, in the flip chip mounting technology, it is required to realize a method of previously providing an insulating adhesive on a circuit board and crimping and connecting a semiconductor chip thereon. At that time, when mounting at a narrow pitch (for example, a pitch of 40 μm or less), it is necessary to use an insulating adhesive containing a flux agent in order to remove the oxide film formed on the surface of the fine circuit wiring of the circuit board. Although required, the present inventors have found that the use of an insulating adhesive containing a flux agent may significantly reduce the insulation reliability of the insulating layer of the circuit board. In this respect, in the present invention in which the resin composition containing the inorganic ion scavenger is used to form the insulating layer in contact with the insulating adhesive, it is possible to suppress deterioration of the insulation reliability of the insulating layer, It will significantly contribute to the further narrow pitch mounting of.

  As the inorganic ion trapping agent, an inorganic cation trapping agent that traps cations by ion exchange, an inorganic anion trapping agent that traps anions by ion exchange, and both cations and anions by ion exchange An inorganic amphoteric ion scavenger is preferable, and an inorganic amphoteric ion scavenger is preferable from the viewpoint of being able to remarkably suppress a decrease in insulation reliability of the insulating layer when an insulating adhesive containing a flux agent is used.

  Examples of the inorganic ion scavenger include one or more oxide hydrates or hydroxides selected from the group consisting of antimony, bismuth, zirconium, titanium, tin, magnesium and aluminum, and bismuth, Two or more kinds of oxide hydrates or hydroxides selected from the group consisting of zirconium, magnesium and aluminum are preferable. Of these, hydrotalcite which is a ternary oxide hydrate of magnesium, aluminum and zirconium, bismuth and a binary oxide hydrate of zirconium and a hydroxide containing magnesium and aluminum is preferable, and hydrotalcite is more preferable. preferable. The inorganic ion scavengers may be used alone or in combination of two or more.

Hydrotalcite is represented by the following formula (1).
Mg _a Al _b (OH) _c (CO ₃ ) _d · nH ₂ O (1)
(In the formula (1), a, b, c, and d are positive numbers and satisfy 2a + 3b-c-2d = 0. In addition, n represents the number of hydration and is 0 or a positive number.)

  In the formula (1), the one obtained by substituting a part of Mg with another divalent metal ion can also be preferably used. Among other divalent metal ions, Zn is particularly preferable.

Specific examples of the hydrotalcite are not particularly limited, but for example, Mg _4.5 Al ₂ (OH) ₁₃ CO ₃ · 3.5H ₂ O, Mg ₅ Al _1.5 (OH) _12.5 CO ₃ ·. _{3.5H 2 O, Mg 6 Al 2} (OH) 16 CO 3 · 4H 2 O, Mg 4.2 Al 2 (OH) 12.4 CO 3 · 3.5H 2 O, Mg 4.3 Al 2 (OH ) _12.6 CO ₃ · 3.5H ₂ O, Mg _2.5 Zn ₂ Al ₂ (OH) ₁₃ CO ₃ · 3.5H ₂ O, Mg _4.2 Al ₂ (OH) _12.4 CO ₃ · 2 _{.5H 2 O, Mg 4.2 Al 2} (OH) 12.4 CO 3 · H 2 O, Mg 4 Al 2 (OH) 12 CO 3 · 3.5H 2 O , and the like. Among these, _{Mg 4.} preferably _{2 Al 2 (OH) 12.4 CO} 3 · 3.5H 2 O

  As the hydrotalcite represented by the formula (1), a / b is preferably 1.5 or more and 5 or less, more preferably 1.7 or more and 3 or less, and 1.8 or more and 2.5. The following is more preferable.

  The average particle size of the inorganic ion scavenger is usually 1 μm or less, preferably 0.8 μm or less, from the viewpoint of being able to remarkably suppress deterioration of insulation reliability of the insulating layer when an insulating adhesive containing a flux agent is used. , And more preferably 0.6 μm or less. The lower limit of the average particle size is not particularly limited, but is preferably 0.01 μm or more, more preferably 0.1 μm or more, still more preferably 0.3 μm or more.

  The average particle size of the inorganic ion scavenger can be measured by a laser diffraction / scattering method based on the Mie scattering theory. Specifically, the particle size distribution of the inorganic ion scavenger is created on a volume basis by a laser diffraction / scattering particle size distribution measuring device, and the median diameter can be used as the average particle diameter for measurement. As the measurement sample, an inorganic ion scavenger dispersed in water by ultrasonic waves can be preferably used. As the laser diffraction / scattering particle size distribution measuring device, "LA-500" manufactured by Horiba, Ltd. or the like can be used.

  The inorganic ion scavenger may be treated (pretreated) with a surface treatment agent such as a silane coupling agent. Specific examples of the surface treatment agent and the degree of the treatment are the same as the surface treatment of the inorganic filler described later, and the preferable range is also the same.

  As the inorganic ion scavenger, a commercially available product may be used, and examples thereof include "IXEPLAS-A1", "IXEPLAS-A2", "IXEPLAS-A3", and "IXEPLAS-B1" manufactured by Toagosei Co., Ltd.

  The content of the inorganic ion scavenger in the resin composition is preferably 0.1 mass from the viewpoint that the deterioration of the insulation reliability of the insulating layer when an insulating adhesive containing a flux agent is used can be significantly suppressed. % Or more, more preferably 0.5% by mass or more, and further preferably 1% by mass or more. The upper limit of the content of the inorganic ion scavenger in the resin composition is preferably 10% by mass or less, more preferably 5% by mass or less, and further preferably 3% by mass or less.

  From the viewpoint of achieving a further narrow-pitch mounting of semiconductor chips, it is possible to remarkably suppress deterioration of insulation reliability of the insulating layer when an insulating adhesive containing a flux agent is used. A) Epoxy resin, (B) curing agent, (C) inorganic filler, and (D) inorganic ion scavenger are contained, the average particle diameter of the (C) component is 3 μm or less, and the average of the (D) component. The particle size is 1 μm or less, and the boiling water absorption rate per hour of a 40 μm thick, 4 cm square cured product obtained by thermosetting the resin composition at 190 ° C. for 90 minutes is 0.6% by mass or less. Is preferred. The present invention also provides the above resin composition, which is particularly suitable for realizing further narrow pitch mounting of semiconductor chips.

  From the viewpoint of realizing further narrow pitch mounting of semiconductor chips without lowering the insulation reliability of the insulating layer, a 40 μm thick, 4 cm square cured product obtained by thermosetting the resin composition of the present invention at 190 ° C. for 90 minutes. Boiling water absorption rate per hour is 0.6% by mass or less, preferably 0.58% by mass or less, more preferably 0.56% by mass or less, still more preferably 0.55% by mass or less, It is 53 mass% or less, 0.51 mass% or less, or 0.5 mass% or less. Although the lower limit of the boiling water absorption is not particularly limited, it can be usually 0.01% by mass or more, 0.1% by mass or more. Here, the boiling water absorption of the cured product represents the rate of mass increase (% by mass) of the cured product when the cured product is immersed in boiling water. In the present invention, a 40 μm thick, 4 cm square cured product obtained by thermosetting the resin composition at 190 ° C. for 90 minutes is used as a test piece, and the boiling water absorption rate per hour of the test piece is evaluated. The boiling water absorption can be measured according to the method described in <Measurement of boiling water absorption> described later.

  Hereinafter, each component contained in the resin composition of the present invention will be described in detail.

<(A) Epoxy resin>
The resin composition of the present invention contains (A) an epoxy resin (also referred to as “(A) component”).

  Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol novolac type epoxy resin, Phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, glycidyl amine type epoxy resin, glycidyl ester type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin Epoxy resin, linear aliphatic epoxy resin, epoxy resin having butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spiro ring-containing Epoxy resins, cyclohexanedimethanol type epoxy resins, naphthylene ether type epoxy resin, trimethylol type epoxy resin, tetraphenyl ethane epoxy resin and the like. The epoxy resins may be used alone or in combination of two or more. The component (A) is preferably one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin, and biphenyl type epoxy resin. A commercially available product may be used as the epoxy resin.

  The epoxy resin preferably contains an epoxy resin having two or more epoxy groups in one molecule. When the non-volatile component of the epoxy resin is 100% by mass, at least 50% by mass or more is preferably an epoxy resin having two or more epoxy groups in one molecule. Above all, having two or more epoxy groups in one molecule, having a liquid epoxy resin at a temperature of 20 ° C. (hereinafter referred to as “liquid epoxy resin”), and having three or more epoxy groups in one molecule, It is preferable to include a solid epoxy resin at a temperature of 20 ° C. (hereinafter referred to as “solid epoxy resin”). By using a liquid epoxy resin and a solid epoxy resin together as the epoxy resin, a resin composition having excellent flexibility can be obtained. Further, the breaking strength of the cured product of the resin composition is also improved.

  As the liquid epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, phenol novolac type epoxy resin, alicyclic epoxy resin having an ester skeleton , And an epoxy resin having a butadiene structure are preferable, and a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol AF type epoxy resin, and a naphthalene type epoxy resin are more preferable. Specific examples of the liquid epoxy resin include “HP4032”, “HP4032D” and “HP4032SS” (naphthalene type epoxy resin) manufactured by DIC Corporation, “828US” and “jER828EL” (bisphenol A) manufactured by Mitsubishi Chemical Corporation. Type epoxy resin), "jER807" (bisphenol F type epoxy resin), "jER152" (phenol novolac type epoxy resin), "YL7760" (bisphenol AF type epoxy resin), "ZX1059" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. ( Mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin), "EX-721" (glycidyl ester type epoxy resin) manufactured by Nagase Chemtex Co., Ltd., "Ceroxide 2021P" (ester skeleton) manufactured by Daicel Corporation. Alicyclic epoxy with Resin), "PB-3600" (epoxy resin having a butadiene structure), Nippon Steel Chemical Co., Ltd. "ZX1658", "ZX1658GS" (liquid 1,4 glycidyl cyclohexane) and the like. These may be used alone or in combination of two or more.

  As the solid epoxy resin, naphthalene type tetrafunctional epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, biphenyl type epoxy resin, naphthylene ether type epoxy resin, Anthracene type epoxy resin, bisphenol A type epoxy resin, and tetraphenylethane type epoxy resin are preferable, and naphthalene type tetrafunctional epoxy resin, naphthol type epoxy resin, and biphenyl type epoxy resin are more preferable. Specific examples of the solid epoxy resin include "HP4032H" (naphthalene type epoxy resin), "HP-4700", "HP-4710" (naphthalene type tetrafunctional epoxy resin) and "N-690" manufactured by DIC Corporation. "(Cresol novolac type epoxy resin)," N-695 "(cresol novolac type epoxy resin)," HP-7200 "," HP-7200HH "," HP-7200H "," HP-7200L "(dicyclopentadiene type) Epoxy resin) "EXA7311", "EXA7311-G3", "EXA7311-G4", "EXA7311-G4S", "HP6000" (naphthylene ether type epoxy resin), "EPPN-502H" manufactured by Nippon Kayaku Co., Ltd. (Trisphenol type epoxy resin), "NC7000L" (Naphthol Volac type epoxy resin), "NC3000H", "NC3000", "NC3000L", "NC3100" (biphenyl type epoxy resin), "ESN475V" (Napthol type epoxy resin), "ESN485" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. (ESN485) ( Naphthol novolac type epoxy resin), "YX4000H", "YL6121" (biphenyl type epoxy resin), "YX4000HK" (bixylenol type epoxy resin), "YX8800" (anthracene type epoxy resin) manufactured by Mitsubishi Chemical Corporation, Osaka Gas Chemical Co., Ltd. “PG-100”, “CG-500”, Mitsubishi Chemical Co., Ltd. “YL7800” (fluorene type epoxy resin), Mitsubishi Chemical Co., Ltd. “jER1010” (solid bisphenol) A type epoxy resin), "jER1031 "(Tetraphenyl ethane epoxy resin) and the like.

  When a liquid epoxy resin and a solid epoxy resin are used in combination as the epoxy resin, their mass ratio (liquid epoxy resin: solid epoxy resin) is in the range of 1: 0.1 to 1: 6 by mass ratio. preferable. By setting the amount ratio of the liquid epoxy resin and the solid epoxy resin in such a range, i) a suitable tackiness is brought about when used in the form of an adhesive film, and ii) when used in the form of an adhesive film Sufficient flexibility is obtained, handleability is improved, and iii) a cured product having sufficient breaking strength can be obtained. From the viewpoint of the above effects i) to iii), the mass ratio of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin: solid epoxy resin) is in the range of 1: 0.3 to 1: 5. Is more preferable, and the range of 1: 0.6 to 1: 4 is further preferable.

  The content of the epoxy resin in the resin composition is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 13% by mass, from the viewpoint of obtaining an insulating layer exhibiting good mechanical strength and insulation reliability. That is all. The upper limit of the content of the epoxy resin is not particularly limited as long as the effects of the present invention are exhibited, but is preferably 50% by mass or less, more preferably 30% by mass or less, and further preferably 20% by mass or less.

  In the present invention, the content of each component in the resin composition is a value when the non-volatile component in the resin composition is 100% by mass, unless otherwise specified.

  The epoxy equivalent of the epoxy resin is preferably 50 to 5000, more preferably 50 to 3000, even more preferably 80 to 2000, and still more preferably 110 to 1000. Within this range, the cross-linking density of the cured product will be sufficient, and an insulating layer having a small surface roughness can be provided. The epoxy equivalent can be measured according to JIS K7236, and is the mass of the resin containing one equivalent of epoxy group.

  The weight average molecular weight of the epoxy resin is preferably 100 to 5000, more preferably 250 to 3000, and further preferably 400 to 1500. Here, the weight average molecular weight of the epoxy resin is a polystyrene equivalent weight average molecular weight measured by a gel permeation chromatography (GPC) method.

<(B) Curing agent>
The resin composition of the present invention contains (B) a curing agent (also referred to as “(B) component”).

  The curing agent is not particularly limited as long as it has a function of curing an epoxy resin, and examples thereof include a phenol curing agent, a naphthol curing agent, an active ester curing agent, a benzoxazine curing agent, a cyanate ester curing agent, and Examples include carbodiimide-based curing agents. The curing agents may be used alone or in combination of two or more. The component (B) preferably contains at least one selected from an active ester-based curing agent and a cyanate ester-based curing agent from the viewpoint of reducing boiling water absorption and improving insulation reliability. A commercially available product may be used as the curing agent.

  The active ester-based curing agent is not particularly limited, but in general, an ester group having a high reaction activity such as phenol ester, thiophenol ester, N-hydroxyamine ester, and ester of heterocyclic hydroxy compound is contained in one molecule. Compounds having two or more of them are preferably used. The active ester type curing agent is preferably obtained by a condensation reaction of a carboxylic acid compound and / or a thiocarboxylic acid compound with a hydroxy compound and / or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester type curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferable, and an active ester type curing agent obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound is more preferable. Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid and pyromellitic acid. Examples of the phenol compound or naphthol compound include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol S, phenolphthaline, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m- Cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, Examples thereof include benzenetriol, dicyclopentadiene type diphenol compound, and phenol novolac. Here, the “dicyclopentadiene-type diphenol compound” refers to a diphenol compound obtained by condensing one molecule of dicyclopentadiene with two molecules of phenol.

  Specifically, an active ester compound containing a dicyclopentadiene type diphenol structure, an active ester compound containing a naphthalene structure, an active ester compound containing an acetylated product of phenol novolac, and an active ester compound containing a benzoylated product of phenol novolac are preferable, Among them, an active ester compound containing a naphthalene structure and an active ester compound containing a dicyclopentadiene type diphenol structure are more preferable. The “dicyclopentadiene type diphenol structure” represents a divalent structural unit composed of phenylene-dicyclopentylene-phenylene.

  Commercially available active ester curing agents include "EXB9451", "EXB9460", "EXB9460S", "HPC8000-65T" (manufactured by DIC Corporation) as active ester compounds containing a dicyclopentadiene type diphenol structure. "EXB9416-70BK" (manufactured by DIC Corporation) as an active ester compound containing a naphthalene structure, "DC808" (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing an acetylated product of phenol novolac, and a benzoylated product of phenol novolac. Examples of the active ester compound to be included include “YLH1026” (manufactured by Mitsubishi Chemical Corporation) and the like.

  Examples of the cyanate ester-based curing agent include bisphenol A dicyanate, polyphenol cyanate, oligo (3-methylene-1,5-phenylene cyanate), 4,4′-methylenebis (2,6-dimethylphenyl cyanate), 4,4. '-Ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenyl propane, 1,1-bis (4-cyanate phenylmethane), bis (4-cyanate-3,5-dimethyl) Phenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, and bifunctional cyanate resin such as bis (4-cyanatephenyl) ether, phenol Novolak and black Polyfunctional cyanate resin derived from tetrazole novolac, these cyanate resins prepolymers and the like obtained by partly triazine of. Specific examples of the cyanate ester-based curing agent include “PT30” and “PT60” (all are phenol novolac type polyfunctional cyanate ester resins) manufactured by Lonza Japan Co., Ltd., “BA230”, and “BA230S75” (of bisphenol A dicyanate). Examples include a prepolymer in which a part or all is triazined into a trimer, and "ULL-950S" (a polyfunctional cyanate ester resin).

  Specific examples of the phenol-based curing agent and the naphthol-based curing agent include, for example, "MEH-7700", "MEH-7810", "MEH-7851" manufactured by Meiwa Kasei Co., Ltd., manufactured by Nippon Kayaku Co., Ltd. "NHN", "CBN", "GPH", "SN170", "SN180", "SN190", "SN475", "SN485", "SN495", "SN375", "SN395" manufactured by Nippon Steel & Sumikin Co., Ltd. , TD-2090-60M, "LA7052", "LA7054", "LA3018", "LA3018-50P", "EXB-9500" and the like manufactured by DIC Corporation.

  Specific examples of the benzoxazine-based curing agent include “HFB2006M” manufactured by Showa Highpolymer Co., Ltd., “Pd” and “Fa” manufactured by Shikoku Chemicals Co., Ltd.

  Specific examples of the carbodiimide-based curing agent include “V-03” and “V-07” manufactured by Nisshinbo Chemical Inc.

  The amount ratio of the epoxy resin and the curing agent is preferably [the total number of epoxy groups of the epoxy resin]: [the total number of reactive groups of the curing agent] in the range of 1: 0.1 to 1: 2, 1: 0.15 to 1: 1.5 are more preferable, and 1: 0.2 to 1: 1 are even more preferable. Here, the reactive group of the curing agent is an active hydroxyl group, an active ester group or the like, and varies depending on the type of the curing agent. Further, the total number of epoxy groups of the epoxy resin is a value obtained by summing the value obtained by dividing the solid content mass of each epoxy resin by the epoxy equivalent for all epoxy resins, and the total number of reactive groups of the curing agent is It is a value obtained by summing the values obtained by dividing the solid content mass of each curing agent by the reactive group equivalent for all curing agents. By setting the amount ratio of the epoxy resin and the curing agent in such a range, the heat resistance of the cured product of the resin composition is further improved.

  The content of the curing agent in the resin composition is not particularly limited, but is preferably 30% by mass or less, more preferably 25% by mass or less, still more preferably 20% by mass or less, still more preferably 18% by mass or less. The lower limit is not particularly limited, but is preferably 3% by mass or more.

<(C) Inorganic filler>
The resin composition of the present invention contains (C) an inorganic filler (hereinafter, also referred to as component (C)).

  The material of the inorganic filler is not particularly limited, for example, silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, water. Aluminum oxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide , Zirconium oxide, barium titanate, barium titanate zirconate, barium zirconate, calcium zirconate, zirconium phosphate, zirconium phosphate tungstate, and the like. Among these, silica is particularly suitable. Spherical silica is preferable as the silica. The inorganic fillers may be used alone or in combination of two or more. A commercially available product may be used as the inorganic filler.

  The average particle size of the inorganic filler is usually 3 μm or less, preferably 2 μm or less, and more preferably 1 μm or less from the viewpoint of realizing further narrow pitch mounting of semiconductor chips. The lower limit of the average particle size is not particularly limited, but is preferably 0.01 μm or more, more preferably 0.1 μm or more, still more preferably 0.3 μm or more. Examples of commercially available inorganic fillers having such an average particle diameter include "YC100C", "YA050C", "YA050C-MJE", "YA010C" manufactured by Admatechs Co., Ltd., manufactured by Denki Kagaku Kogyo Co., Ltd. Examples include "UFP-30", "Silfill NSS-3N" manufactured by Tokuyama Corporation, "Silfill NSS-4N", "Silfill NSS-5N", "SOC2" and "SOC1" manufactured by Admatechs Co., Ltd.

  The average particle diameter of the inorganic filler can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, the particle size distribution of the inorganic filler can be created on a volume basis using a laser diffraction / scattering particle size distribution measuring device, and the median diameter can be used as the average particle diameter for measurement. As the measurement sample, an inorganic filler dispersed in water by ultrasonic waves can be preferably used. As the laser diffraction / scattering particle size distribution measuring device, "LA-500" manufactured by Horiba, Ltd. or the like can be used.

  The inorganic filler is an aminosilane coupling agent, an epoxysilane coupling agent, a mercaptosilane coupling agent, a silane coupling agent, an organosilazane compound, a titanate coupling agent, from the viewpoint of improving moisture resistance and dispersibility. It is preferably treated with one or more surface treatment agents such as Examples of commercially available surface treatment agents include "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. and "KBM803" (3-mercaptopropyltrimethoxy manufactured by Shin-Etsu Chemical Co., Ltd.). Silane), Shin-Etsu Chemical Co., Ltd. “KBE903” (3-aminopropyltriethoxysilane), Shin-Etsu Chemical Co., Ltd. “KBM573” (N-phenyl-3-aminopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd. "SZ-31" (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM103" (phenyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. "KBM-4803" (long-chain epoxy type) manufactured by Shin-Etsu Chemical Co., Ltd. Silane coupling agent) and the like.

The degree of surface treatment with the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. Carbon content per unit surface area of the inorganic filler, from the viewpoint of improving dispersibility of the inorganic filler is preferably 0.02 mg / ^{m 2} or more, 0.1 mg / ^{m 2} or more preferably, 0.2 mg / ^{m 2} The above is more preferable. On the other hand, from the viewpoint of preventing the melt viscosity of the resin varnish and the melt viscosity in the sheet form from increasing, 1 mg / m ² or less is preferable, 0.8 mg / m ² or less is more preferable, and 0.5 mg / m ² or less is further preferable. preferable.

  The amount of carbon per unit surface area of the inorganic filler can be measured after cleaning the surface-treated inorganic filler with a solvent (for example, methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler surface-treated with the surface treatment agent, and ultrasonic cleaning is performed at 25 ° C. for 5 minutes. After removing the supernatant and drying the solid content, the carbon amount per unit surface area of the inorganic filler can be measured using a carbon analyzer. As the carbon analyzer, "EMIA-320V" manufactured by HORIBA, Ltd. can be used.

  From the viewpoint of obtaining an insulating layer having a low coefficient of thermal expansion, the content of the inorganic filler in the resin composition is preferably 50% by mass or more, more preferably 60% by mass or more, and further preferably 65% by mass or more. The upper limit of the content of the inorganic filler in the resin composition is preferably 95 mass% or less, more preferably 90 mass% or less, further preferably 85 mass% or less, or 80 mass from the viewpoint of the mechanical strength of the insulating layer. % Or less.

<(D) Inorganic ion scavenger>
The resin composition of the present invention contains (D) an inorganic ion scavenger (also referred to as “(D) component”).

  The average particle diameter of the component (D) is usually 1 μm or less from the viewpoint that the deterioration of the insulation reliability of the insulating layer when an insulating adhesive containing a flux agent is used can be significantly suppressed. Details of the component (D) such as a suitable range of the average particle size are as described above.

<(E) Thermoplastic resin>
The resin composition of the present invention preferably contains a thermoplastic resin (E) (also referred to as “(E) component”) in addition to the components (A) to (D).

  Examples of the thermoplastic resin include phenoxy resin, polyvinyl acetal resin, polyolefin resin, polybutadiene resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, polycarbonate resin, and polyether. Examples include ether ketone resins and polyester resins, with phenoxy resins being preferred. The thermoplastic resins may be used alone or in combination of two or more. A commercially available product may be used as the thermoplastic resin.

  The polystyrene-equivalent weight average molecular weight of the thermoplastic resin is preferably in the range of 8,000 to 70,000, more preferably in the range of 10,000 to 60,000, and even more preferably in the range of 20,000 to 60,000. The polystyrene equivalent weight average molecular weight of the thermoplastic resin is measured by gel permeation chromatography (GPC) method. Specifically, the polystyrene-equivalent weight average molecular weight of the thermoplastic resin is LC-9A / RID-6A manufactured by Shimadzu Corporation as a measuring device, and Shodex K-800P / K-manufactured by Showa Denko KK as a column. 804L / K-804L can be calculated by using chloroform as a mobile phase, measuring the column temperature at 40 ° C., and using a calibration curve of standard polystyrene.

  Examples of the phenoxy resin include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenolacetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, terpene. Examples include phenoxy resins having one or more skeletons selected from the group consisting of a skeleton and a trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group and an epoxy group. The phenoxy resin may be used alone or in combination of two or more. Specific examples of the phenoxy resin include "1256" and "4250" (both are bisphenol A skeleton-containing phenoxy resins) manufactured by Mitsubishi Chemical Corporation, "YX8100" (bisphenol S skeleton-containing phenoxy resin), and "YX6954" ( Bisphenol acetophenone skeleton-containing phenoxy resin), and in addition, "FX280" and "FX293" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., "YX6954BH30", "YX7553", "YX7553BH30" manufactured by Mitsubishi Chemical Corporation, "YL7769BH30", "YL6794", "YL7213", "YL7290", "YL7482" and the like can be mentioned.

  Examples of the polyvinyl acetal resin include polyvinyl formal resin and polyvinyl butyral resin, and polyvinyl butyral resin is preferable. Specific examples of the polyvinyl acetal resin include, for example, Denki Kagaku Kogyo Co., Ltd., "Electrical butyral 4000-2", "Electrical butyral 5000-A", "Electrical butyral 6000-C", "Electrical butyral 6000-EP". The S-REC BH series, BX series, KS series, BL series, and BM series manufactured by Sekisui Chemical Co., Ltd. may be mentioned.

  Specific examples of the polyimide resin include "Ricacoat SN20" and "Ricacoat PN20" manufactured by Shin Nippon Rika Co., Ltd. Specific examples of the polyimide resin also include a linear polyimide obtained by reacting a bifunctional hydroxyl group-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride (polyimide described in JP 2006-37083 A), a polysiloxane skeleton. Modified polyimides such as contained polyimides (polyimides described in JP-A No. 2002-12667 and JP-A No. 2000-319386) can be mentioned.

  Specific examples of the polyamide-imide resin include “Vylomax HR11NN” and “Vylomax HR16NN” manufactured by Toyobo Co., Ltd. Specific examples of the polyamideimide resin also include modified polyamideimides such as "KS9100" and "KS9300" (polysiloxane skeleton-containing polyamideimide) manufactured by Hitachi Chemical Co., Ltd.

  Specific examples of the polyether sulfone resin include "PES5003P" manufactured by Sumitomo Chemical Co., Ltd. and the like.

  Specific examples of the polysulfone resin include polysulfone “P1700” and “P3500” manufactured by Solvay Advanced Polymers Co., Ltd.

  Among them, phenoxy resin and polyvinyl acetal resin are preferable as the thermoplastic resin. Therefore, in a preferred embodiment, the component (E) includes at least one selected from the group consisting of a phenoxy resin and a polyvinyl acetal resin.

  The content of the thermoplastic resin in the resin composition is preferably 0.1% by mass to 20% by mass, more preferably 0.5% by mass to 10% by mass, and further preferably 1% by mass to 5% by mass. .

<(F) Curing accelerator>
The resin composition of the present invention preferably contains (F) a curing accelerator (also referred to as “(F) component”) in addition to components (A) to (D).

  Examples of the curing accelerator include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, metal-based curing accelerators, phosphorus-based curing accelerators, amine-based curing accelerators, and the like. A curing accelerator, an imidazole curing accelerator, and a metal curing accelerator are preferable, and an amine curing accelerator, an imidazole curing accelerator, and a metal curing accelerator are more preferable. The curing accelerator may be used alone or in combination of two or more. A commercially available product may be used as the curing accelerator.

  Examples of phosphorus-based curing accelerators include triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl) triphenylphosphonium thiocyanate. , Tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, and the like, and triphenylphosphine and tetrabutylphosphonium decanoate are preferable.

  Examples of the amine curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6, -tris (dimethylaminomethyl) phenol, 1,8-diazabicyclo. Examples include (5,4,0) -undecene, and 4-dimethylaminopyridine and 1,8-diazabicyclo (5,4,0) -undecene are preferable.

  Examples of the imidazole-based curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl- Two Phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl- (1 ′)]-Ethyl-s-triazine, 2,4-diamino-6- [2′-ethyl-4′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino- 6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl- 4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 1-dodecyl-2-methyl Examples thereof include imidazole compounds such as 3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline, and adducts of imidazole compounds and epoxy resins, such as 2-ethyl-4-methylimidazole and 1-benzyl-2-phenyl. Imidazole is preferred.

  As the imidazole-based curing accelerator, a commercially available product may be used, and examples thereof include "P200-H50" manufactured by Mitsubishi Chemical Corporation.

  Examples of the guanidine-based curing accelerator include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1- (o-tolyl) guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, Tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo [4.4.0] dec-5-ene, 7-methyl-1,5,7-triazabicyclo [4.4.0] Deca-5-ene, 1-methyl biguanide, 1-ethyl biguanide, 1-n-butyl biguanide, 1-n-octadecyl biguanide, 1,1-dimethyl biguanide, 1,1-diethyl biguanide, 1-cyclohexyl biguanide, 1 -Allyl biguanide, 1-phenyl biguanide, 1- ( - tolyl) biguanide, and the like, dicyandiamide, 1,5,7-triazabicyclo [4.4.0] dec-5-ene are preferred.

  Examples of the metal-based curing accelerator include organic metal complexes or salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of the organic metal complex include organic cobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organic copper complexes such as copper (II) acetylacetonate, and zinc (II) acetylacetonate. And the like, organic iron complexes such as iron (III) acetylacetonate, organic nickel complexes such as nickel (II) acetylacetonate, and organic manganese complexes such as manganese (II) acetylacetonate. Examples of the organic metal salt include zinc octylate, tin octylate, zinc naphthenate, cobalt naphthenate, tin stearate, zinc stearate and the like.

  The content of the curing accelerator in the resin composition is not particularly limited, but when the total amount of the nonvolatile components of the epoxy resin and the curing agent is 100% by mass, use in the range of 0.05% by mass to 3% by mass. Is preferred.

<(G) Flame retardant>
The resin composition of the present invention may contain (G) a flame retardant (also referred to as “(G) component”) in addition to components (A) to (D). Examples of the flame retardant include organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants, metal hydroxides, and the like. The flame retardants may be used alone or in combination of two or more, and may be commercially available products.

  Examples of the flame retardant include "HCA-HQ" manufactured by Sanko Co., Ltd. and the like.

  The content of the flame retardant in the resin composition is not particularly limited, but is preferably 0.5% by mass to 20% by mass, more preferably 0.5% by mass to 15% by mass, and further preferably 0.5% by mass to. 10% by mass is more preferable.

<(H) Organic filler>
The resin composition of the present invention may further contain (H) an organic filler (also referred to as “(H) component”) from the viewpoint of improving elongation, in addition to the components (A) to (D). As the component (H), any organic filler that can be used in forming the insulating layer of the circuit board may be used, and examples thereof include rubber particles, polyamide fine particles, and silicone particles. Good.

  As the rubber particles, commercially available products may be used, and examples thereof include "EXL-2655" manufactured by Dow Chemical Japan Co., Ltd. and "AC3816N" manufactured by Ganz Kasei Co., Ltd.

  The content of the (H) component in the resin composition is preferably 0.1% by mass to 20% by mass, more preferably 0.2% by mass to 10% by mass, further preferably 0.3% by mass to 5% by mass. %, Or 0.5% by mass to 3% by mass.

  The resin composition may further contain other additives, if necessary.As such other additives, for example, organocopper compounds, organozinc compounds and organometallic compounds such as organocobalt compounds, In addition, organic fillers, thickeners, defoamers, leveling agents, adhesion promoters, and resin additives such as colorants may be used.

  As described above, by forming the insulating layer of the circuit board using the resin composition of the present invention, the insulation reliability of the insulating layer when the insulating adhesive containing the flux agent is used in flip chip mounting of the semiconductor chip. Of the semiconductor chips can be remarkably suppressed, and further narrow pitch mounting of the semiconductor chips can be realized. Therefore, the resin composition of the present invention can be suitably used for forming an insulating layer in contact with an insulating adhesive containing a flux agent of a circuit board in the production of a semiconductor chip package. The resin composition of the present invention is also suitable for a wide range of other applications requiring high insulation reliability, for example, for forming an insulating layer of a circuit board such as a printed wiring board on which a semiconductor chip package is mounted. Can be used for Therefore, in one embodiment, the resin composition of the present invention can be used for an insulating layer of a circuit board. In a more preferred embodiment, the resin composition of the present invention can be used for an insulating layer when the circuit board is an interposer.

[Sheet-like laminated material]
When manufacturing the semiconductor chip package, the resin composition of the present invention can be applied in the form of a varnish and used, but it is preferable to use it in the form of a sheet-like laminated material containing a layer of the resin composition.

  As the sheet-shaped laminated material, the following adhesive film and prepreg are preferable.

  In one embodiment, the adhesive film comprises a support and a resin composition layer (adhesive layer) bonded to the support, and the resin composition layer (adhesive layer) is the resin composition of the present invention. Formed from.

  The thickness of the resin composition layer is preferably 100 μm or less, more preferably 80 μm or less, further preferably 60 μm or less, still more preferably 50 μm or less or 40 μm or less from the viewpoint of thinning. The lower limit of the thickness of the resin composition layer is not particularly limited, but it can be usually 1 μm or more, 5 μm or more, 10 μm or more.

  Examples of the support include a film made of a plastic material, a metal foil and a release paper, and a film made of a plastic material and a metal foil are preferable. A commercially available product may be used as the support.

  When a film made of a plastic material is used as the support, the plastic material may be, for example, polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”) or polyethylene naphthalate (hereinafter simply referred to as “PEN”). .) Etc., polycarbonate (hereinafter sometimes abbreviated as “PC”), acrylic such as polymethylmethacrylate (PMMA), cyclic polyolefin, triacetyl cellulose (TAC), polyether sulfide (PES), polyether. Examples include ketones and polyimides. Among them, polyethylene terephthalate and polyethylene naphthalate are preferable, and inexpensive polyethylene terephthalate is particularly preferable.

  When a metal foil is used as the support, examples of the metal foil include copper foil and aluminum foil, and copper foil is preferable. As the copper foil, a foil made of a single metal of copper may be used, and a foil made of an alloy of copper and another metal (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium) is used. You may use.

  The support may have a matte treatment or a corona treatment applied to the surface to be joined to the resin composition layer.

  Further, as the support, a support with a release layer having a release layer on the surface to be joined with the resin composition layer may be used. Examples of the release agent used in the release layer of the support with release layer include one or more release agents selected from the group consisting of alkyd resin, polyolefin resin, urethane resin, and silicone resin. . The support with release layer may be a commercially available product, for example, "SK-1" manufactured by Lintec Co., Ltd., which is a PET film having a release layer containing an alkyd resin release agent as a main component. , “AL-5”, “AL-7”, “Lumirror T6AM” manufactured by Toray Industries, Inc., and the like.

  The thickness of the support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, more preferably in the range of 10 μm to 60 μm. When a support with a release layer is used, the total thickness of the support with a release layer is preferably within the above range.

  For the adhesive film, for example, a resin varnish prepared by dissolving a resin composition in an organic solvent is prepared, and the resin varnish is applied onto a support using a die coater or the like, and further dried to form a resin composition layer. It can be manufactured.

  Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone (MEK) and cyclohexanone, ethyl acetate, butyl acetate, cellosolve acetate, acetic acid esters such as propylene glycol monomethyl ether acetate and carbitol acetate, cellosolve and butyl carbitol. Carbitols, aromatic hydrocarbons such as toluene and xylene, amide solvents such as dimethylformamide, dimethylacetamide (DMAc) and N-methylpyrrolidone. The organic solvent may be used alone or in combination of two or more.

  Drying may be performed by a known method such as heating or blowing hot air. The drying conditions are not particularly limited, but the resin composition layer is dried so that the content of the organic solvent is 10% by mass or less, preferably 5% by mass or less. Although it varies depending on the boiling point of the organic solvent in the resin varnish, for example, when using a resin varnish containing 30% by mass to 60% by mass of the organic solvent, the resin composition is dried at 50 ° C to 150 ° C for 3 minutes to 10 minutes. An object layer can be formed.

  In the adhesive film, a protective film conforming to the support can be further laminated on the surface of the resin composition layer that is not bonded to the support (that is, the surface opposite to the support). The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, it is possible to prevent dust and the like from adhering to the surface of the resin composition layer and prevent scratches. The adhesive film can be wound into a roll and stored. When the adhesive film has a protective film, it can be used by peeling off the protective film. As the protective film, a commercially available product may be used, and examples thereof include "Alphan MA-430" manufactured by Oji Ftex Co., Ltd. and the like.

  In one embodiment, the prepreg is formed by impregnating a sheet-shaped fiber base material with the resin composition of the present invention.

  The sheet-shaped fiber base material used for the prepreg is not particularly limited, and those commonly used as the base material for prepreg such as glass cloth, aramid nonwoven fabric, liquid crystal polymer nonwoven fabric and the like can be used. From the viewpoint of reducing the thickness of the circuit board, the thickness of the sheet-shaped fiber base material is preferably 50 μm or less, more preferably 40 μm or less, further preferably 30 μm or less, still more preferably 20 μm or less. The lower limit of the thickness of the sheet-shaped fiber base material is not particularly limited, but is usually 10 μm or more.

  The prepreg can be manufactured by a known method such as a hot melt method or a solvent method.

  The thickness of the prepreg may be in the same range as the resin composition layer in the above-mentioned adhesive film.

  The sheet-shaped laminated material of the present invention can be suitably used for forming an insulating layer of a circuit board in the production of a semiconductor chip package. The sheet-shaped laminated material of the present invention is also used for a wide range of other applications requiring high insulation reliability, for example, for forming an insulating layer of a circuit board such as a printed wiring board on which a semiconductor chip package is mounted. It can be used preferably. Therefore, in one embodiment, the sheet-shaped laminated material of the present invention can be used for an insulating layer of a circuit board. In a more preferred embodiment, the sheet-shaped laminated material of the present invention can be used for an insulating layer when the circuit board is an interposer.

[Method of manufacturing semiconductor chip package]
The manufacturing method of the semiconductor chip package of the present invention,
(I) a step of providing an insulating adhesive containing a flux agent on a circuit board including an insulating layer made of a cured product of the resin composition, and (II) a step of joining a semiconductor chip to the circuit board,
And an insulating layer in contact with the insulating adhesive containing a flux agent is formed of a cured product of a resin composition containing an inorganic ion scavenger.

-Process (I)-
In step (I), an insulating adhesive containing a flux agent is provided on a circuit board including an insulating layer made of a cured product of the resin composition.

  When the circuit board includes a plurality of insulating layers, the insulating layer in contact with the insulating adhesive containing a flux agent may be an insulating layer made of a cured product of a resin composition containing an inorganic ion scavenger. As the insulating layer that does not come into contact with the insulative adhesive containing, an insulating layer made of a cured product of a known resin composition may be used. "Contacting" means a state in which an insulating layer is laminated adjacent to an insulating adhesive containing a flux agent, and even when an embedded wiring is provided between the insulating adhesive and the insulating layer. Including.

  In the present invention which uses a circuit board including an insulating layer formed of a cured product of a resin composition containing an inorganic ion scavenger, the insulating reliability of the insulating layer when an insulating adhesive containing a flux agent is used is improved. It can be suppressed, and can significantly contribute to the further narrow pitch mounting of the semiconductor chip.

  The circuit board used in the step (I) is not particularly limited as long as the insulating layer in contact with the insulating adhesive containing the flux agent is an insulating layer made of a cured product of a resin composition containing an inorganic ion scavenger. Although the resin composition containing the inorganic ion scavenger is as described above, it is possible to remarkably suppress a decrease in insulation reliability of the insulating layer when an insulating adhesive containing a flux agent is used. From the viewpoint of realizing further narrow pitch mounting of chips, the resin composition contains (A) an epoxy resin, (B) a curing agent, (C) an inorganic filler, and (D) an inorganic ion scavenger. The component (C) has an average particle size of 3 μm or less, the component (D) has an average particle size of 1 μm or less, and the resin composition is thermally cured at 190 ° C. for 90 minutes. The boiling water absorption rate of the cured product per hour is preferably 0.6% by mass or less. The details of each component and the preferable range of boiling water absorption are as described above.

  The circuit board has circuit wiring. In the present invention using a resin composition containing an inorganic ion scavenger, it is possible to remarkably suppress a decrease in insulation reliability of an insulating layer when an insulating adhesive containing a flux agent is used, and thus a fine circuit. It is possible to use a circuit board having wiring. For example, it is possible to use a circuit board having circuit wiring with a ratio (L / S) of the circuit width (line; L) to the width (space; S) between circuits of 20 μm / 20 μm or less (that is, wiring pitch of 40 μm or less). Is. Furthermore, it is possible to use a circuit board having circuit wirings with L / S = 15 μm / 15 μm or less (wiring pitch 30 μm or less) and L / S = 10 μm / 10 μm or less (wiring pitch 20 μm or less). The wiring pitch of the circuit wiring does not have to be the same throughout the circuit board. The present inventors have found that when the minimum pitch of circuit wiring is 40 μm or less, the insulation reliability of the insulating layer tends to be significantly reduced when an insulating adhesive containing a flux agent is used. It was In this respect, in the present invention using a resin composition containing an inorganic ion scavenger, even when using a circuit board having a circuit wiring with a narrow pitch as described above, the insulation reliability of the insulating layer is reduced. It can be advantageously suppressed. In a preferred embodiment in which the effects of the present invention can be more enjoyed, the circuit board has circuit wiring with a minimum pitch of 40 μm or less. The wiring pitch refers to the distance P that is the sum of the conductor layer 31 (line) and the circuit width (space), as shown in FIG.

  In the present invention using a resin composition containing an inorganic ion scavenger, even when a circuit board having fine embedded wiring is used, it is possible to advantageously suppress deterioration in insulation reliability of the insulating layer. In the present invention, the minimum pitch of the embedded wiring may be 40 μm or less, 30 μm or less, or 20 μm or less.

  The circuit board used in the step (I) is preferably a coreless board from the viewpoint of thinning. The coreless board is a circuit board that does not include the core board, and can reduce the overall thickness and the signal processing time. Therefore, in a preferred embodiment, the circuit board is a coreless board. Particularly, a coreless substrate having a structure in which one circuit wiring is embedded in one insulating layer is more preferable.

  In a particularly preferred embodiment that can enjoy the effects of the present invention, the circuit board is a coreless board having embedded wiring with a minimum pitch of 40 μm or less. The method of manufacturing the circuit board will be described later.

  In the step (I), the insulating adhesive containing the flux agent may be provided in a paste state or a film state. When the insulating adhesive is provided in a paste state, it may be applied on the circuit board by using, for example, a die coater or a bar coater. When the insulating adhesive is provided in the form of a film, it may be laminated by a vacuum laminating method as in the case of laminating a resin composition layer described later. The flux agent refers to a component capable of chemically removing the oxide film formed on the surface of the circuit wiring on the semiconductor chip mounting surface of the circuit board. For example, an organic acid, a halogen salt of an amine compound, or an amine compound An organic acid salt is mentioned. When using a circuit board with narrow-pitch circuit wiring to mount semiconductor chips in a narrow pitch, use an insulating adhesive containing a flux agent to obtain good conductor connection between the semiconductor chip and the circuit board. There is a need to.

  The thickness of the insulating adhesive may be determined according to the desired design of the semiconductor chip package, and may be, for example, 100 μm or less, 90 μm or less, 80 μm or less, or 70 μm. Although the lower limit is not particularly limited, it can be usually 1 μm or more and 5 μm or more.

  The insulating adhesive containing the flux agent is not particularly limited, and known insulating adhesives can be used. For example, the insulating adhesive containing the flux agent described in Japanese Patent No. 4204865 can be used.

  In the present invention in which the resin composition containing the inorganic ion scavenger is used to form the insulating layer of the circuit board, the flux agent is sufficient to sufficiently remove the oxide film formed on the surface of the circuit wiring with a narrow pitch. Even when the insulating adhesive containing is used, it is possible to suppress deterioration of the insulating reliability of the insulating layer. For example, the content of the flux agent in the insulating adhesive may be 2% by mass or more, 5% by mass or more, or 10% by mass or more. In addition, a commercially available product may be used as the insulating adhesive containing the flux agent, and examples of the commercially available product include “LOCTITE ECCOBOND NCP 5208” manufactured by Henkel.

The circuit board used in the step (I) is as described above, and the manufacturing method thereof is not particularly limited. For example, when manufacturing a coreless board as a circuit board,
(I) a step of laminating a dry film on a support substrate and forming a pattern on the dry film (ii) a step of forming a conductor layer and peeling the dry film (iii) a support substrate on which the conductor layer is formed Circuit board by a manufacturing method including a step of providing a resin composition containing an inorganic ion scavenger and thermosetting the resin composition to form an insulating layer (iv) peeling a supporting substrate to produce a circuit board Can be manufactured.

  In step (i), a dry film 21 is laminated on the support substrate 11 and a pattern is formed on the dry film 21 as shown in FIG. In FIG. 1, the surface of the support substrate 11 is provided with a first metal layer 12 and a second metal layer 13 made of a metal such as copper foil. In FIG. 1, the dry film 21 is laminated on both sides of the support substrate 11 and the pattern is formed on the dry film 21, but the dry film 21 is laminated only on one surface of the support substrate 11 and the dry film 21 is formed. 21 may be patterned.

  The support substrate is not particularly limited as long as steps (i) to (iv) can be carried out. Examples of the supporting substrate include a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, and the like. As shown in FIG. A metal layer such as a foil (first metal layer 12, second metal layer 13) may be formed.

  The dry film is not particularly limited as long as it is a photosensitive dry film made of a photoresist composition, and for example, a dry film of novolac resin, acrylic resin or the like can be used. A commercially available product may be used as the dry film, and for example, “ALPHO 20A263” manufactured by Nikko Material Co., Ltd., which is a dry film with a PET film, can be used. The dry film may be laminated on one surface of the supporting substrate or may be laminated on both surfaces of the supporting substrate.

  The conditions for laminating the support substrate and the dry film are the same as the conditions for laminating in the step (iii) described below, and the preferable ranges are also the same.

  After laminating the dry film on the support substrate, exposure and development are performed under predetermined conditions using a photomask in order to form a desired pattern on the dry film.

  In step (ii), a conductor layer is formed and the dry film is peeled off. Here, the conductor layer can be formed by a plating method using a dry film having a desired pattern as a plating mask. For details, as shown in an example in FIG. 2, the conductor film 31 is formed on the support substrate 11 (second metal layer 13) using the dry film 21 having a desired pattern as a plating mask.

  The conductor material used for the conductor layer is not particularly limited. In a preferred embodiment, the conductor layer is one or more selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin and indium. Including metal. The conductor layer may be a single metal layer or an alloy layer. As the alloy layer, for example, an alloy of two or more kinds of metals selected from the above group (for example, nickel-chromium alloy, copper. Layers formed from nickel alloys and copper-titanium alloys). Among them, from the viewpoint of versatility of conductor layer formation, cost, easiness of patterning, etc., a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or a nickel-chromium alloy, copper. A nickel alloy or an alloy layer of copper / titanium alloy is preferable, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or an alloy layer of nickel / chromium alloy is more preferable, and a single layer of copper is preferable. Metal layers are more preferred.

  The thickness of the conductor layer depends on the desired design of the semiconductor chip package, but is preferably 3 μm to 35 μm, more preferably 5 μm to 30 μm, still more preferably 7 to 20 μm, or 15 μm.

  As shown in FIG. 3 as an example, after forming the conductor layer 31, the dry film is peeled off. The peeling of the dry film can be carried out using, for example, an alkaline peeling liquid such as a sodium hydroxide solution. If necessary, an unnecessary conductor layer can be removed by etching or the like to form a conductor layer having a desired wiring pattern. The pitch P of the wiring to be formed is as described above.

  In the step (iii), a resin composition containing an inorganic ion scavenger is provided on the supporting substrate on which the conductor layer is formed, and the resin composition is thermoset to form an insulating layer. The resin composition may be provided in a varnish state or may be provided by using the above-mentioned sheet-shaped laminated material. Hereinafter, as shown in FIG. 4, an embodiment in which an adhesive film is used to provide a resin composition on a supporting substrate will be described. In such an embodiment, the adhesive film 40 having the resin composition layer 41 and the support 42 is provided on the support substrate 11 on which the conductor layer 31 is formed, and the resin composition layer 41 of the adhesive film 40 is the conductor layer 31. It is laminated so as to be bonded to.

  The lamination of the adhesive film can be performed, for example, by thermocompression bonding the adhesive film to the conductor layer from the support side. Examples of the member (hereinafter, also referred to as “thermocompression bonding member”) for thermocompression bonding the adhesive film to the conductor layer include a heated metal plate (SUS end plate or the like) or a metal roll (SUS roll). It is preferable that the thermocompression-bonding member is not directly pressed onto the adhesive film, but is pressed via an elastic material such as heat-resistant rubber so that the adhesive film sufficiently follows the surface irregularities of the conductor layer.

  The lamination of the adhesive film may be performed by a vacuum laminating method. In the vacuum laminating method, the thermocompression bonding temperature is preferably in the range of 60 ° C. to 160 ° C., more preferably 80 ° C. to 140 ° C., and the thermocompression bonding pressure is preferably 0.098 MPa to 1.77 MPa, more preferably 0. It is in the range of 0.29 MPa to 1.47 MPa, and the thermocompression bonding time is preferably in the range of 20 seconds to 400 seconds, more preferably 30 seconds to 300 seconds. Lamination is preferably carried out under reduced pressure conditions with a pressure of 13 hPa or less.

  Lamination can be performed by a commercially available vacuum laminator. Examples of the commercially available vacuum laminator include a vacuum pressure laminator manufactured by Nikko Materials Co., Ltd., a vacuum pressure laminator manufactured by Meiki Seisakusho, and a vacuum applicator manufactured by Nichigo Morton Co., Ltd.

  After laminating, the smoothing treatment of the laminated adhesive film may be performed under normal pressure (under atmospheric pressure), for example, by pressing a thermocompression bonding member from the support side. The press conditions for the smoothing treatment can be the same as the above-mentioned thermocompression bonding conditions for the lamination. The smoothing treatment can be performed with a commercially available laminator. The lamination and smoothing treatment may be continuously performed using the above-mentioned commercially available vacuum laminator.

  The support may be removed before laminating the adhesive film or after laminating.

  After the resin composition layer is laminated, the resin composition layer is thermoset to form an insulating layer. The thermosetting conditions of the resin composition layer are not particularly limited, and the conditions usually adopted when forming the insulating layer of the circuit board may be used.

  For example, the thermosetting conditions of the resin composition layer vary depending on the type of the resin composition and the like, but the curing temperature is in the range of 120 ° C to 240 ° C (preferably 150 ° C to 220 ° C, more preferably 170 ° C). The curing time may be in the range of 5 minutes to 120 minutes (preferably 10 minutes to 100 minutes, more preferably 15 minutes to 90 minutes).

  Before thermosetting the resin composition layer, the resin composition layer may be preheated at a temperature lower than the curing temperature. For example, prior to thermosetting the resin composition layer, the resin composition layer is formed at a temperature of 50 ° C. or higher and lower than 120 ° C. (preferably 60 ° C. or higher and 110 ° C. or lower, more preferably 70 ° C. or higher and 100 ° C. or lower). Preheating may be performed for 5 minutes or more (preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes).

  In another embodiment, the present invention can be manufactured by using a prepreg instead of the above adhesive film. The manufacturing method is basically the same as when an adhesive film is used.

If necessary, the formation of the conductor layer and the insulating layer in the steps (i) to (iii) may be repeatedly performed to form a multilayer wiring layer. When forming a multi-layered wiring layer, (1) a step of forming a hole in the insulating layer, (2) a step of roughening the insulating layer, and (3) a step of forming a conductor layer may be further performed. These steps (1) to (3) may be carried out according to various methods known to those skilled in the art used for manufacturing a printed wiring board.
When using a multilayer wiring board, a resin composition containing an inorganic ion scavenger may be used for all insulating layers, but only on the outermost layer on the side to which the insulating adhesive containing a flux agent is applied. The resin composition may be used.

  The step (1) is a step of drilling a hole in the insulating layer, whereby holes such as via holes and through holes can be formed in the insulating layer. The step (1) may be carried out by using, for example, a drill, a laser, plasma or the like depending on the composition of the resin composition used for forming the insulating layer. The size and shape of the hole may be appropriately determined according to the design of the circuit board.

  Step (2) is a step of roughening the insulating layer. The procedure and conditions of the roughening treatment are not particularly limited, and known procedures and conditions usually used when forming the insulating layer of the circuit board can be adopted. For example, the insulating layer can be roughened by performing swelling treatment with a swelling liquid, roughening treatment with an oxidizing agent, and neutralization treatment with a neutralizing liquid in this order. The swelling liquid is not particularly limited, and examples thereof include an alkaline solution and a surfactant solution, preferably an alkaline solution, and the alkaline solution is more preferably a sodium hydroxide solution or a potassium hydroxide solution. Examples of commercially available swelling liquids include “Swelling Dip Securigans P” and “Swelling Dip Securigans SBU” manufactured by Atotech Japan Co., Ltd. The swelling treatment with the swelling liquid is not particularly limited, but can be performed, for example, by immersing the insulating layer in the swelling liquid at 30 ° C. to 90 ° C. for 1 minute to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the cured product in a swelling liquid at 40 ° C. to 80 ° C. for 5 minutes to 15 minutes. The oxidizing agent is not particularly limited, and examples thereof include an alkaline permanganate solution obtained by dissolving potassium permanganate or sodium permanganate in an aqueous solution of sodium hydroxide. The roughening treatment with an oxidizing agent such as an alkaline permanganate solution is preferably performed by immersing the insulating layer in the oxidizing agent solution heated to 60 ° C to 80 ° C for 10 minutes to 30 minutes. The concentration of permanganate in the alkaline permanganate solution is preferably 5% by mass to 10% by mass. Examples of commercially available oxidizing agents include alkaline permanganate solutions such as “Concentrate Compact CP” and “Dosing Solution Securigans P” manufactured by Atotech Japan Co., Ltd. The neutralizing solution is preferably an acidic aqueous solution, and examples of commercially available products include “Reduction Solution Securigant P” manufactured by Atotech Japan Co., Ltd. The treatment with the neutralizing solution can be performed by immersing the treated surface roughened with the oxidizing agent in the neutralizing solution at 30 ° C to 80 ° C for 5 minutes to 30 minutes. From the viewpoint of workability and the like, it is preferable to immerse the object roughened with the oxidizing agent in a neutralizing solution at 40 ° C to 70 ° C for 5 to 20 minutes. As the swelling liquid and the oxidizing agent, commercially available products may be used.

  The arithmetic average roughness Ra of the surface of the insulating layer after the roughening treatment is preferably 300 nm or less, more preferably 280 nm or less, still more preferably 260 nm or less, 240 nm or less, 220 nm or less, or 200 nm or less. Although the lower limit of Ra is not particularly limited, it can usually be 1 nm or more, 3 nm or more, 5 nm or more. The arithmetic average roughness (Ra) of the surface of the insulating layer can be measured using a non-contact surface roughness meter. A specific example of the non-contact type surface roughness meter is “WYKO NT3300” manufactured by Bee Coin Instruments.

  Step (3) is a step of forming a conductor layer.

  The conductor material used for the conductor layer is the same as the conductor layer used in the step (ii), and the preferable range is also the same.

  The thickness of the conductor layer is the same as that of the conductor layer used in the step (ii), and the preferable range is also the same.

  The conductor layer may be formed by plating. For example, a conductor layer having a desired wiring pattern can be formed by plating the surface of the insulating layer by a conventionally known technique such as a semi-additive method or a full-additive method. Hereinafter, an example of forming the conductor layer by the semi-additive method will be described.

  First, a plating seed layer is formed on the surface of the insulating layer by electroless plating. Next, a mask pattern that exposes a part of the plating seed layer corresponding to a desired wiring pattern is formed on the formed plating seed layer. After forming a metal layer on the exposed plating seed layer by electrolytic plating, the mask pattern is removed. After that, the unnecessary plating seed layer can be removed by etching or the like to form a conductor layer having a desired wiring pattern.

  In the step (iv), as shown in FIG. 5, the supporting substrate is peeled off to produce a circuit board. The method for peeling the supporting substrate is not particularly limited. When an unnecessary conductor layer is present on the surface of the circuit board, the conductor layer may be removed by etching or the like.

  Therefore, the method for manufacturing a semiconductor chip package of the present invention may include the above steps (i) to (iv) before the step (I).

-Step (II)-
In step (II), the semiconductor chip is bonded to the circuit board.

  The bonding conditions are not particularly limited as long as the terminal electrodes of the semiconductor chip are conductively connected to the circuit wiring of the circuit board, and known conditions used in flip-chip mounting of the semiconductor chip may be used.

One preferred embodiment crimps a semiconductor chip to a circuit board. As the crimping conditions, for example, the crimping temperature is in the range of 120 ° C. to 240 ° C. (preferably in the range of 130 ° C. to 200 ° C., more preferably in the range of 140 ° C. to 180 ° C.), and the crimping time is in the range of 1 second to 60 seconds. (Preferably 5 seconds to 30 seconds).
In another preferred embodiment, the semiconductor chip is reflowed and bonded to the circuit board. The reflow condition may be, for example, in the range of 120 ° C to 300 ° C.

  In the present invention in which the resin composition containing the inorganic ion scavenger is used to form the insulating layer of the circuit board, the semiconductor chips can be mounted at a narrow pitch without lowering the insulation reliability of the insulating layer. For example, the minimum pitch of the terminal electrodes of the semiconductor chip may be 40 μm or less, 30 μm or less, or 20 μm or less.

The semiconductor chip package manufactured by the method of the present invention includes a circuit board including an insulating layer made of a cured product of the resin composition of the present invention. Therefore, even when a semiconductor chip is mounted using an insulating adhesive containing a flux agent, good insulation reliability is exhibited. In one embodiment, a semiconductor chip package manufactured by the method of the present invention is 100 hours when subjected to an advanced accelerated life test (HAST) at 130 ° C., 85% RH (relative humidity) and a bias voltage of 3.3V. The subsequent insulation resistance value is 1.0 × 10 ⁷ Ω or more. The insulation reliability can be measured, for example, according to the method described in <Measurement of insulation reliability> described later.

[Semiconductor device]
The semiconductor device on which the semiconductor chip package of the present invention is mounted includes electric products (for example, computers, mobile phones, digital cameras and televisions) and vehicles (for example, motorcycles, automobiles, trains, ships and aircrafts). There are various semiconductor devices used for such purposes.

  Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. In the following description, “parts” and “%” mean “parts by mass” and “mass%”, respectively, unless otherwise specified.

[Measurement method / Evaluation method]
First, various measurement methods and evaluation methods will be described. The thicknesses of the adhesive film and the prepreg were measured using a contact-type layer thickness gauge (“MCD-25MJ” manufactured by Mitutoyo Corporation).

<Preparation of evaluation board>
(1) Lamination of dry film on supporting substrate As a supporting substrate, a glass cloth base material epoxy resin double-sided copper clad laminate (layer composition: Mitsui Mining & Smelting Co., Ltd. Microthin MT-Ex copper foil (thickness 3 μm) Copper foil / 18 μm thick carrier foil) / Panasonic Corporation “R1515A” substrate (0.2 mm thick) / Mitsui Mining & Smelting Co., Ltd. Micro Thin MT-Ex copper foil (18 μm thick carrier foil / A copper foil having a thickness of 3 μm)) was prepared. A dry film with a PET film (“ALPHO 20A263” manufactured by Nikko Materials Co., Ltd., dry film thickness 20 μm) is bonded to the copper foil on both sides of the 3 μm copper foil of the laminate. As described above, the layers were laminated using a batch type vacuum pressure laminator (two-stage build-up laminator “CVP700” manufactured by Nikko Materials Co., Ltd.). The lamination of the dry film was performed by depressurizing for 30 seconds so that the atmospheric pressure was 13 hPa or less, and then pressure-bonding for 20 seconds at a temperature of 70 ° C. and a pressure of 0.1 MPa.

(2) Pattern formation A glass mask (photomask) on which a wiring pattern shown below is formed is placed on a PET film which is a protective layer of a dry film, and UV irradiation is performed with a UV lamp at an irradiation intensity of 150 mJ / cm ² . did. After UV irradiation, the PET film as a dry film was peeled off, and a 1% sodium carbonate aqueous solution at 30 ° C. was sprayed at an injection pressure of 0.15 MPa for 30 seconds. Then, it was washed with water and the dry film was developed (pattern formation).

Glass mask wiring pattern:
・ L / S = 15 μm / 15 μm, that is, a comb pattern with a wiring pitch of 30 μm (wiring length 15 mm, 16 lines)
・ The number of comb patterns is 7 pieces

(3) Formation of Conductor Layer After development of the dry film, electrolytic copper plating was performed to a thickness of 15 μm to form a conductor layer. Then, a 3% sodium hydroxide solution at 50 ° C. was spray-treated at an injection pressure of 0.2 MPa, the dry film was peeled off, washed with water, and dried at 150 ° C. for 30 minutes.

(4) Lamination of Adhesive Film Next, the protective films of the adhesive films produced in the examples and comparative examples were peeled off, and the batch type vacuum pressure laminator (Nikko Materials Co., Ltd. two-stage build-up laminator “CVP700”) was used. Was laminated on both surfaces of the substrate so that the resin composition layer was bonded to the conductor layer. The lamination was performed by reducing the pressure for 30 seconds so that the atmospheric pressure was 13 hPa or less, and then performing pressure bonding for 30 seconds at 100 ° C. and a pressure of 0.74 MPa. Next, the laminated adhesive film was subjected to hot pressing at 100 ° C. and a pressure of 0.5 MPa under atmospheric pressure for 60 seconds to be smoothed.

(5) Thermosetting of Resin Composition Layer After laminating the adhesive film, the resin composition layer is thermoset under conditions of 100 ° C. for 30 minutes and then 175 ° C. for 30 minutes to form insulating layers on both surfaces of the conductor layer. did. Then, the support (release PET film) was peeled off to expose the insulating layer.

(6) Lamination of prepreg The protective film of the prepreg for the evaluation board is peeled off on the circuit board with the insulating layer exposed, and the batch type vacuum pressure laminator (Nikko Materials Co., Ltd. 2-stage build-up laminator "CVP700") is laminated. ) Was laminated on both surfaces of the circuit board so that the resin composition layer of the prepreg was bonded to the insulating layer. The lamination was performed by reducing the pressure for 30 seconds so that the atmospheric pressure was 13 hPa or less, and then performing pressure bonding for 30 seconds at 120 ° C. and a pressure of 0.74 MPa. Then, it was smoothed by hot pressing under atmospheric pressure at 120 ° C. and a pressure of 0.5 MPa for 60 seconds.
The prepreg for the evaluation substrate was manufactured as follows.

(Preparation of prepreg for evaluation board)
5 parts of liquid naphthalene type epoxy resin (epoxy equivalent 144, "HP4032SS" manufactured by DIC Corporation), bisphenol type epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical Co., Ltd., 1: 1 of bisphenol A type and bisphenol F type) Mixed product, epoxy equivalent 169) 5 parts, biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC3000L", epoxy equivalent 269) 20 parts, phenoxy resin (Mitsubishi Chemical Co., Ltd. "YX7553BH30", solid content 30 mass % Of MEK and cyclohexanone (1: 1 solution) was dissolved in 15 parts of solvent naphtha with stirring while heating. What was heated and dissolved was cooled to room temperature, and a triazine skeleton-containing phenolic curing agent (“LA3018-50P” manufactured by DIC Corporation, hydroxyl equivalent of about 151, 2-methoxypropanol solution with solid content of 50%) 10 Parts, phenol novolac-based curing agent (“TD-2090-60M” manufactured by DIC Corporation, MEK having hydroxyl equivalent of about 105, solid content 60%) 11 parts, curing accelerator (4-dimethylaminopyridine (DMAP), solid 2 parts by mass of MEK solution (2% by mass), flame retardant (“HCA-HQ” manufactured by Sanko Co., Ltd.), 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenance. Ren-10-oxide, average particle size 2 μm) 2 parts, and phenylaminosilane-based coupling agent (Shin-Etsu Chemical Co., Ltd., “KBM573”) Treated spherical silica (average particle size 0.5 [mu] m, (Ltd.) Admatechs Ltd. "SOC2", carbon content 0.39 mg ^/ m 2 per unit area) 90 parts, were mixed, uniformly dispersed in a high-speed rotary mixer Then, a resin varnish was produced.

  Then, a glass cloth (1037NS, thickness: 23 μm) manufactured by Arisawa Seisakusho Co., Ltd. was dipped and impregnated in the above resin varnish by a solvent method to evaporate the solvent by heating, and the amount of the solvent remaining in the prepreg was 0.5. %, And the thickness was dried to 50 μm. A release PET film (“AL5” manufactured by Lintec Co., Ltd., thickness: 38 μm) on one surface of the prepreg and a protective film (polypropylene film, “Alphan MA-430” manufactured by Oji Ftex Co., Ltd.) on the other surface. , Thickness of 20 μm) were pasted together with a hot roll to prepare a prepreg.

(7) Thermosetting of prepreg After laminating the prepreg, the resin composition layer was thermoset under conditions of 100 ° C. for 30 minutes and 180 ° C. for 30 minutes to form insulating layers on both surfaces of the circuit board. Then, the release PET film was peeled off.

(8) Separation of Supporting Substrate The supporting substrate was peeled and separated at the interface between a copper foil having a thickness of 3 μm and a carrier foil having a thickness of 18 μm, which is Microthin MT-Ex copper foil manufactured by Mitsui Mining & Smelting Co., Ltd.

(9) Fabrication of Substrate with Embedded Wiring of L / S = 15/15 μm Comb Tooth Pattern A 3 μm copper foil on the surface layer was removed by etching with an aqueous copper chloride solution, washed with water, and then heat-cured at 190 ° C. for 90 minutes to obtain L. A substrate having embedded wiring of / S = 15/15 μm comb tooth pattern (wiring pitch 30 μm) was produced.

(10) Application of Insulating Adhesive, Thermal Curing An insulating adhesive containing an acidic flux agent (LOCTITE ECCOBOND NCP 5208, made by Henkel) is formed to a thickness of about 70 μm so as to cover the obtained comb tooth pattern. It was applied by bar coating and heat cured at 80 ° C. for 60 minutes and 160 ° C. for 120 minutes.

<Measurement of insulation reliability>
Using an advanced accelerated life test device (“PM422” manufactured by Kusumoto Kasei Co., Ltd.), the evaluation substrates manufactured as described above were subjected to accelerated environmental tests for 100 hours and 150 hours. The conditions of the accelerated environment test were 130 ° C., 85% RH, and 3.3 V applied. After the accelerated environment test, the insulation resistance value (Ω) of the evaluation substrate was measured with an electrochemical migration tester (“ECM-100” manufactured by J-RAS Co., Ltd.). The insulation resistance value (Ω) was evaluated according to the following evaluation criteria.
Evaluation criteria:
◯: In the accelerated environment test of 100 hours and 150 hours, all 7 pieces were 1.0 × 10 ⁷ Ω or more. Δ: In the accelerated environment test of 100 hours, all 7 pieces were 1.0 × 10 ⁷ Ω or more. , One or more of the ^seven pieces were less than 1.0 × 10 ⁷ Ω in the accelerated environment test for 150 hours ×: One or more of the ^seven pieces were 1.0 × in the accelerated environment test for 100 hours Less than 10 ⁷ Ω

<Measurement of boiling water absorption>
The adhesive films prepared in Examples and Comparative Examples were heated at 190 ° C. for 90 minutes to thermally cure the resin composition layer, and then the release PET film was peeled off. The obtained cured product (thickness 40 μm) is referred to as “cured product for evaluation”. The cured product for evaluation was cut into a 4 cm square test piece, and the test piece was dried at 130 ° C. for 30 minutes and then weighed (this weighed mass is referred to as A (g)). The test piece was immersed in boiled ion-exchanged water for 1 hour. After that, the test piece was immersed in ion-exchanged water at room temperature (25 ° C.) for 1 minute, and the test piece was wiped off with a clean wiper (manufactured by Clarke Flex Co., Ltd.) and weighed (weighed this). The mass is B (g)). The boiling water absorption of each of the five test pieces was determined from the following formula, and the average value is shown in the table below.
Boiled water absorption (mass%) = ((B−A) / A) × 100

<Example 1>
10 parts of bisphenol type epoxy resin (“ZX1059” manufactured by Nippon Steel Chemical Co., Ltd., 1: 1 mixture of bisphenol A type and bisphenol F type, epoxy equivalent 169), biphenyl type epoxy resin (manufactured by Nippon Kayaku Co., Ltd.) 20 parts of "NC3000L", 20 parts of epoxy equivalent 269, 10 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, MEK (methyl ethyl ketone) having a solid content of 30% by mass and cyclohexanone), and 20 parts of solvent naphtha. It was heated and dissolved with stirring. What was heated and dissolved was cooled to room temperature, and then an active ester compound (“HPC8000-65T” manufactured by DIC Corporation, weight average molecular weight of about 2700, active group equivalent of about 223, toluene solution of nonvolatile content 65% by mass) ) 10 parts, triazine skeleton-containing phenolic curing agent ("LA3018-50P" manufactured by DIC Corporation, hydroxyl equivalent of about 151, solid content 50% 2-methoxypropanol solution) 10 parts, curing accelerator (4-dimethylamino) Pyridine (DMAP), 3 parts of MEK solution having a solid content of 2% by mass, and 2 parts of rubber particles (AC3816N manufactured by Ganz Kasei Co., Ltd.) were swelled in 10 parts of solvent naphtha at room temperature for 12 hours, a flame retardant. (“HCA-HQ” manufactured by Sanko Co., Ltd., 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphuff. Spherical silica (average particle size 0.5 μm, surface-treated with 2 parts of nanthrene-10-oxide, average particle size 2 μm) and a phenylaminosilane-based coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM573”). Co. Admatechs Co. "SOC2" carbon amount per unit area 0.39 mg ^/ m 2) 0.99 parts, inorganic ion scavenger (manufactured by Toagosei Co., Ltd. "IXEPLAS-A3", Mg, Al, Zr-based, Resin varnish 1 was prepared by mixing 5 parts of a primary particle diameter of 0.5 μm and surface treatment agent) and uniformly dispersing with a high-speed rotary mixer.

  Then, a resin varnish was uniformly applied on the release surface of the polyethylene terephthalate film with a release treatment so that the thickness of the dried resin composition layer was 40 μm, and the coating was performed at 80 to 120 ° C. (average 100 ° C.) for 4 hours. After drying for 5 minutes, a protective film (polypropylene film, "Alphan MA-430" manufactured by Oji Ftex Co., Ltd., thickness 20 μm) was attached so as to be bonded to the resin composition layer, and the adhesive film 1 was attached. It was made. Here, the adhesive film for use in <Measurement of boiling water absorption rate> uses “PET501010” (thickness 50 μm) manufactured by Lintec Co., Ltd. as a support, and is used for adhesion in <Production of evaluation substrate>. As the film, "AL-5" (thickness 38 µm) manufactured by Lintec Co., Ltd. was used as a support.

<Example 2>
10 parts of bisphenol type epoxy resin (“ZX1059” manufactured by Nippon Steel Chemical Co., Ltd., 1: 1 mixture of bisphenol A type and bisphenol F type, epoxy equivalent 169), biphenyl type epoxy resin (manufactured by Nippon Kayaku Co., Ltd.) 20 parts of "NC3000L", epoxy equivalent 269), 15 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, MEK having a solid content of 30 mass% and a 1: 1 solution of cyclohexanone) are stirred in 15 parts of solvent naphtha. While heating and dissolving. What was heated and dissolved was cooled to room temperature, and then an active ester compound (“HPC8000-65T” manufactured by DIC Corporation, weight average molecular weight of about 2700, active group equivalent of about 223, toluene solution of nonvolatile content 65% by mass) ) 15 parts, triazine skeleton-containing phenolic curing agent ("LA3018-50P" manufactured by DIC Corporation, hydroxyl equivalent about 151, solid content 50% 2-methoxypropanol solution) 10 parts, curing accelerator (4-dimethylamino) Pyridine (DMAP), 4 parts of solid content 2% by weight MEK solution), flame retardant (“HCA-HQ” manufactured by Sanko Co., Ltd., 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-). 2 parts of 10-phosphaphenanthrene-10-oxide, average particle size 2 μm, and phenylaminosilane-based coupling agent (Shin-Etsu Chemical Co., Ltd. ) Made, "KBM573") surface-treated with spherical silica (average particle size 0.24 .mu.m, (Ltd.) Admatechs Ltd. "SOC1", carbon content per unit area 0.36 mg ^/ m 2) 120 parts of inorganic ion 1 part of a scavenger (“IXEPLAS-A2” manufactured by Toagosei Co., Ltd., Mg, Al, Zr system, primary particle diameter 0.2 μm) was mixed and uniformly dispersed with a high-speed rotary mixer to prepare a resin varnish 2. did. Then, in the same manner as in Example 1, an adhesive film 2 was produced.

<Example 3>
Liquid naphthalene type epoxy resin (epoxy equivalent 144, DIC Corporation "HP4032SS") 5 parts, bixylenol type epoxy resin (Mitsubishi Chemical Corporation "YX4000HK", epoxy equivalent about 185) 5 parts, dicyclopentadiene type 10 parts of epoxy resin ("HP-7200H" manufactured by DIC Corporation, epoxy equivalent 275), phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, 1: 1 solution of MEK and cyclohexanone having a solid content of 30 mass%) 5 Parts were dissolved by heating in 15 parts of solvent naphtha while stirring. What was heated and dissolved was cooled to room temperature, and then an active ester compound (“HPC8000-65T” manufactured by DIC Corporation, weight average molecular weight of about 2700, active group equivalent of about 223, toluene solution of nonvolatile content 65% by mass) ) 6 parts, a prepolymer of bisphenol A dicyanate ("BA230S75" manufactured by Lonza Japan Co., Ltd., a cyanate equivalent of about 232, a MEK solution having a nonvolatile content of 75% by mass) 12 parts, a polyfunctional cyanate ester resin (manufactured by Lonza Japan Co., Ltd.) "ULL-950S", cyanate equivalent of about 235, non-volatile content 75 mass% MEK solution 12 parts, curing accelerator (4-dimethylaminopyridine (DMAP), solid content 2 mass% MEK solution) 1 part, curing acceleration Agent (Tokyo Kasei Co., Ltd., cobalt (III) acetylacetonate (CO (III) Ac), solid 3 parts of 1% by mass MEK solution, flame retardant (“HCA-HQ” manufactured by Sanko Co., Ltd.), 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene. -10-oxide, average particle size 2 μm) 2 parts, and spherical silica (average particle size 0.5 μm, (KBM573, manufactured by Shin-Etsu Chemical Co., Ltd.) surface-treated with spherical silica (average particle size 0.5 μm, ( Ltd.) Admatechs Co. "SOC2" carbon amount per unit area 0.39 mg ^/ m 2) 90 parts of an inorganic ion scavenger (manufactured by Toagosei Co., Ltd. "IXEPLAS-B1", Bi, Al-based, primary particle size (0.4 μm) 1.5 parts were mixed and uniformly dispersed by a high speed rotation mixer to prepare a resin varnish 3. Then, in the same manner as in Example 1, an adhesive film 3 was produced.

<Example 4>
10 parts of bisphenol type epoxy resin (“ZX1059” manufactured by Nippon Steel Chemical Co., Ltd., 1: 1 mixture of bisphenol A type and bisphenol F type, epoxy equivalent 169), biphenyl type epoxy resin (manufactured by Nippon Kayaku Co., Ltd.) 20 parts of "NC3000L", epoxy equivalent 269), 10 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, MEK having a solid content of 30 mass% and a cyclohexanone 1: 1 solution) are stirred in 20 parts of solvent naphtha. While heating and dissolving. What was heated and dissolved was cooled to room temperature, and a triazine skeleton-containing phenolic curing agent (“LA3018-50P” manufactured by DIC Corporation, hydroxyl equivalent of about 151, 2-methoxypropanol solution with solid content of 50%) 10 Parts, phenol novolac-based curing agent (“TD-2090-60M” manufactured by DIC Corporation, MEK having hydroxyl equivalent of about 105, solid content 60%) 11 parts, curing accelerator (4-dimethylaminopyridine (DMAP), solid 2 parts by weight of MEK solution (2% by mass), 2 parts of rubber particles (manufactured by Ganz Kasei Co., Ltd., AC3816N) were allowed to swell in 10 parts of solvent naphtha for 12 hours at room temperature, flame retardant (manufactured by Sanko Co., Ltd.) "HCA-HQ", 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide 2 parts of average particle size 2 μm) and spherical silica (average particle size 0.5 μm, manufactured by Admatechs Co., Ltd.) surface-treated with a phenylaminosilane-based coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM573”) "SOC2", carbon content 0.39 mg ^/ m 2) 0.99 parts per unit area, the inorganic ion scavenger (manufactured by Toagosei Co., Ltd. "IXEPLAS-A3", a primary particle diameter of 0.5 [mu] m, with a surface treatment) 5 parts Were mixed and uniformly dispersed with a high-speed rotary mixer to prepare a resin varnish 4. Then, in the same manner as in Example 1, an adhesive film 4 was produced.

<Comparative Example 1>
In Example 1, 5 parts of the inorganic ion scavenger (“IXEPLAS-A3” manufactured by Toagosei Co., Ltd., primary particle diameter 0.5 μm, with surface treatment) was not used. A resin varnish 5 and an adhesive film 5 were produced in the same manner as in Example 1 except for the above matters.

<Comparative example 2>
In Example 3, 1.5 parts of the inorganic ion scavenger (“IXEPLAS-B1” manufactured by Toagosei Co., Ltd., primary particle size 0.4 μm) was not used. A resin varnish 6 and an adhesive film 6 were produced in the same manner as in Example 3 except for the above matters.

11 Support Substrate 12 First Metal Layer 13 Second Metal Layer 21 Dry Film 31 Conductor Layer 40 Adhesive Film 41 Resin Composition Layer (Insulating Layer)
42 Support P Pitch

Claims (23)

(I) a step of providing an insulating adhesive containing a flux agent on a circuit board including an insulating layer made of a cured product of the resin composition, and (II) a step of joining a semiconductor chip to the circuit board,
A resin containing (D) an inorganic ion trapping agent having an average particle size of 1 μm or less and (C) an inorganic filler having an average particle size of 3 μm or less, A method for producing a semiconductor chip package, which comprises a cured product of the composition. A resin composition containing an inorganic ion scavenger contains (A) epoxy resin, (B) curing agent, (C) inorganic filler, and (D) inorganic ion scavenger ,
40μm thickness obtained by the resin composition was cured for 90 minutes heat at 190 ° C., boiling water absorption per hour of the cured product of 4cm angle is less 0.6 wt%, The method of claim 1.   The method according to claim 2, wherein the component (B) contains at least one selected from an active ester curing agent and a cyanate ester curing agent. (C) component comprises silica, method according to any one of claims 1-3. (D) component, antimony, bismuth, zirconium, titanium, tin, one or more oxide hydrates or hydroxides selected from the group consisting of magnesium and aluminum, either Claim 1-4 The method according to item 1. The method according to any one of claims 1 to 5, wherein the component (D) contains two or more kinds of oxide hydrates or hydroxides selected from the group consisting of bismuth, zirconium, magnesium and aluminum.   The method according to claim 1, wherein the circuit board has a circuit wiring having a minimum pitch of 40 μm or less.   The method according to claim 1, wherein the circuit board has embedded wiring. Before step (I)
(I) a step of laminating a dry film on a support substrate and forming a pattern on the dry film (ii) a step of forming a conductor layer and peeling the dry film (iii) a support substrate on which the conductor layer is formed A step of providing a resin composition containing an inorganic ion scavenger and thermosetting the resin composition to form an insulating layer. (Iv) A step of peeling a supporting substrate to produce a circuit board. 8. The method according to any one of item 8. A resin composition containing (A) an epoxy resin, (B) a curing agent, (C) an inorganic filler, and (D) an inorganic ion scavenger,
The average particle diameter of the component (C) is 3 μm or less,
The average particle size of the component (D) is 1 μm or less,
A resin composition having a boiling water absorption rate of 0.6% by mass or less per hour for a 40 μm thick, 4 cm square cured product obtained by thermosetting the resin composition at 190 ° C. for 90 minutes.   The resin composition according to claim 10, wherein the component (B) contains at least one selected from an active ester curing agent and a cyanate ester curing agent.   The resin composition according to claim 10 or 11, wherein the component (C) contains silica.   The component (D) contains any one or more oxide hydrates or hydroxides selected from the group consisting of antimony, bismuth, zirconium, titanium, tin, magnesium and aluminum. The resin composition according to Item 1.   The resin composition according to any one of claims 10 to 13, wherein the component (D) contains two or more kinds of oxide hydrates or hydroxides selected from the group consisting of bismuth, zirconium, magnesium and aluminum. .   The resin composition according to any one of claims 10 to 14, which is for an insulating layer of a circuit board. (I) providing an insulating adhesive containing a flux agent on the circuit board, and (II) joining a semiconductor chip to the circuit board,
The resin composition according to any one of claims 10 to 15, which is used in a method for producing a semiconductor chip package, which comprises:   The resin composition according to claim 15 or 16, wherein the circuit board is an interposer.   A sheet-shaped laminated material, comprising a layer of the resin composition according to claim 10.   A circuit board, wherein a surface on which a semiconductor chip is mounted is formed of an insulating layer made of a cured product of the resin composition according to any one of claims 10 to 17.   The circuit board according to claim 19, wherein the circuit board is a coreless board.   The circuit board according to claim 19 or 20, wherein the insulating layer formed of a cured product of the resin composition is a single layer.   The circuit board according to claim 19, wherein the minimum pitch of circuit wiring is 40 μm or less.   A semiconductor chip package in which a semiconductor chip is mounted on the circuit board according to any one of claims 19 to 22 via an insulating adhesive containing a flux agent.

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